So the cell grows in a co-ordinated manner:
When cells move or grow, they must add new membrane to those growth regions, says Vavylonis. The process of membrane delivery is called exocytosis. Cells also must deliver this membrane to a specific location in order to maintain a sense of direction?called “polarization”?or grow in a coordinated manner.
“We demonstrated that these processes are coupled: local excess of exocytosis causes some of the proteins attached to the membrane to move (‘flow’) away from the growth region,” says Vavylonis. “These proteins that move away mark the non-growing cell region, thus establishing a self-sustaining pattern, which gives rise to the tubular shape of these yeast cells.”
This is the first time that this mechanism for cell patterning?the process by which cells acquire spatial nonuniformities on their surfaces?has been identified…
“Our work shows that patterns in biological systems are generally not static,” says Rutkowski. “Patterns establish themselves through physical processes involving continuous flow and turnover.”Lehigh University, “How do cells acquire their shapes? A new mechanism identified” at ScienceDaily (September 17, 2021)
The paper is open access.